Polymeric acenaphthylene and methods of preparing the same



Patented June 6, 1950 UNITED STATES PATENT OFFICE POLYMERIC ACENAPHTHYLENE AND METHODS OF PREPARING THE SAME- Harry F. Miller and Ralph 0. Flowers, Plttllield, has, assignors to General Electric Company, a corporation oi New York No Drawing. Original application September 26, 1944, Serial No. 555,895.

Divided and this application April 1,/ 1948, Serial No. 18,487

This application is a division or our copending application Serial No. 555,895, now U. 3. Patent 2,445,181, died September 26, 1944, and assigned I to the same assignee as the present application.

The present invention relates generally to the production 01 polymers and copolymers of acenaphthylene. More specifically, the invention is concerned with the production of high molecular weight polymers of acenaphthylene and copolymers o! acenaphthylene with compounds containing at least one polymerizable CH2=C grouping. Acenaphthylene, which is an unsaturated hydrocarbon of the formula.

' lation purposes.

Copolymers may also be produced in accordance with the present invention by polymerizing acenaphthylene with any compound containing at least one polymeriz'able CH2=C grouping, illustrative examples of which are: vinyl compounds such as vinyl carbazole, vinyl ethers, vinyl esters, vinyl halides, vinyl phthalainide, acrylic acid, acrylic acid esters, methacrylic acid esters, acrylic acid nitrile: unsaturated hydrocarbons such as isoprene, vinyl acetylene, butadiene, isobutylene; propenyl methyl ketone; polymerizable aryl compounds having one or more unsaturated side chains such as p-methoxy-propenyl benzene, propenyl benzene, o-hydroxy styrene, divinyl benzene,

and isoeugenol. Indene and indene derivatives also may be copolymerized with acenaphthylene. In order that those skilled in the art better may understand how the present invention may be carried into elfect, the following examples are given by way t illustration. All parts are by weight.

' Example 1 A slow stream of BF; gas was passed through -6 Claims. (CL 280-33.?)

an ether solution of acenaphthylene containing 8.9 parts 01 the hydrocarbon at C., the solution being allowed to warm up to 25 C. Alter standing four hours a precipitate formed. The polymer was reprecipitated from a benzene solution with methyl alcohol. Molecular weightdeterminations on the different chain length fractions of the polymer showed values of 183,000 and 341,000. Molecular weight measurements were made by the Mead and Fuoss method described in Jour. Phys. Chem, vol. 4'7, No. 1, January 1843, pp. 59-70.

Example 2 15 parts acenaphthylene in parts (by volume) chlorbenzene were cooled to approximately 0 C. and BF: gas bubbled slowly through the solution. A white powder was obtained on dilution of the chlorbenzene solution with methyl alcohol. This product did not flow at 220 C.

under a pressure of 30,000 pounds which is indicative of very high molecular weight polymers.

Example 3 31 parts of acenaphthylene in chlorbenzene solution were polymerized with a, slow stream oi BF: gas. The temperature was held below 0 C. for the reaction period (15 minutes) and a white product was obtained on dilution with methyl alcohol. This polymer was plasticized with Dowtherm A (diphenyl-diphenylene oxide eutectic mixture) and coated on 0.0004" plain kraft paper. After two weeks in an 80 C. oven the polyacenaphthylene coated paper still retained its original pliability.

Example 4 37 parts oi a very high molecular weight polymer were obtained by polymerizing-at 15 to 20 0., for 30 minutes, 50 parts of acenaphthylene in parts (by volume) chlorbenzene with a very slow current of BF: gas. The polymer, which was a white product, was plastlcized with o-methylnaphthalene and coated on 0.0004" k'rai't paper. A laminated product was made by pressing together at C. and 20,000 ounds pressure 7 sheets of this polyacenaphthylene coated paper and used as the dielectric material in a capacitor. Measurements made on the capacitor showed an initial dielectric constant of 4.15 and power factors of 1.4% and 0.84% at 28 C. and 85 C. respectively. Leakage resistances at 28 C. and 85 C. were, respectively, 2,390,000 ohms/cm. and 210- 000 ohms/cm.

Example 5 89 parts polyacenaphthylene were mixed with 20 parts polystyrene and 20 parts of a-methyl naphthalene as plasticizer in 400 parts (by volume) of trichloroethylene. The solution was used to coat 0.0004" kraft paper which was built up to 0.0012" with the resin. "The material was laminated by stacking six sheets and pressing at 150-160" C. and 15,000 pounds pressure. The resulting product is a transparent sheet useful in making high frequency capacitors.

Example 6 9 parts acenaphthylene and 29 parts of vinyl carbazole were refluxed in benrene as a solvent and benzoyl peroxide as the catalyst for 48 hours in an oil bath at 100 C. The copolymer, twice precipitated from a benzene solution with methyl alcohol, was flesh colored and did not soften on the 200 0. hot plate. Nitrogen analysis showed the copolymer contained 19% acenaphthylene. An infrared absorption spectrum taken on this material as well as on pure polyvinyl carbazole and pure polyacenaphthylene showed that the product was a true copolymer. The copolymer is particularly adapted for use in high frequency electrical applications.

Example 7 30- parts of vinyl carbazole were copolymerized with parts of acenaphthylene using benzoyl peroxide as the catalyst and benzene as the solvent, by heating in an oil bath at 100 C. for several days. The product was precipitated from the benzene solution as a white powder which did not melt on the 200 0. hot plate.

Example 8 500 parts of vinyl carbazaole and 155 parts of acenaphthylene were copolymerized using benzoyl peroxide as the catalyst and benzene (650 parts by volume) as the solvent by heating the mixture for 168 hours in an oil bath at 105 C. The product, a white powder, was precipitated from the benzene solution, did not melt on the 200 C. hot plate, and was used to coat paper as described in Example 4.

Example 9 5 parts of acenaphthylene were copoiymerized with 10 parts of styrene at about 0 C. using BF: gas for 30 minutes. This copolymer when coated on paper, possessed good laminating properties.

Example 10 1 part of acenaphthylene and 9 parts of vinyl acetate were copolymerized at 100 C. with benzoyl peroxide as the catalyst and precipitated as a white powder with methyl alcohol.

Example 11 1 part of acenaphthylene and 9 parts of methyl methacrylate were copolymerized at 100 C. using benzoyl peroxide as the catalyst. The product, precipitated from solution with methyl alcohol, was a white powder.

It will be understood by those skilled in the art that the invention is not limited to the production of copolymers of acenaphthylene with the particular compounds given in the above illustrative examples. Any compound containing at least one polymerizable CH2=C grouping, numerous examples of which have hereinbefore been mentioned, may be used. In certain cases, instead of polymerizing a single organic compound containing a polymerizable CH2=C grouping, the acenaphthylene may be oopolymerized with a centration will be within the range of 0.1 to 1.0% 1

by weight of the whole. The rate of polymerization and the properties of the final product vary with the time, temperature and with the catalyst and its concentration. Polymerizations may be effected at various temperatures depending on the catalyst used.

The proportions of 'monomeric constituents used in preparing the various copolymer products of the present invention are not restricted to the proportions given in the above examples. Various proportions of monomers may be used in preparing the copolymers, depending upon the type, of copolymer desired and the use to which it is to be put.

The polymers and copolymers of the present invention may be used alone or with fillers, plasticizers .or other modifying bodies compatible therewith. As noted in the examples, the high molecular weight polymers of this invention, as well as the copolymers. are adaptedrfor use in coating paper and the like, for the production of laminated dielectric material for use in electrical, devices, such as capacitors, the polymers and copolymers of the present invention being particularly adapted for use in high frequency electrical applications where high heat resistance is desired.

What we claim as new and desire to secur by LettersPatent of the United States is:

1. The method which comprises passing boron trifluoride through a solution of acenaphthylene at a temperature ranging from 0 to 5 0 0., and adding a non-solvent to the resulting solution thereby to obtain a high molecular weight polymer of acenaphthylene having a molecular weight between 150,000 and 341,000 when measured by the osmotic pressure method.

2. The method which comprises passing gaseous boron trifluoride, through a chlorobenzene solution of acenaphthylene at a temperature of 0 0., and adding methyl alcohol to the resulting solution thereby to obtain a high molecular weight polymer of acenaphthylene having a. molecular weight between 150,000 and 341,000 when measured by the osmotic pressure method.

3. The method of making a homopolymer of acenaphthylene which comprises passing gaseous boron trifluoride through a solution of acenaphthylene at a temperature ranging from 0 C. to -50 C. until a high molecular weight polymer of acenaphthylene is obtained, the said homopolymer having a molecular weight ranging from 150,000 to 341,000 when measured by the osmotic pressure method.

4. Homopolymeric acenaphthylene having a molecular weight of from 150,000 to 341,000 when measured by the osmotic pressure method and prepared by passing boron trifluoride through a solution of acenaphthylene at a temperature ranging from 0 to -50 0., and adding a nonsolvent to the resulting solution thereby to obtain the aforementioned high molecular weight poly- UNITED STATES I'A'IENTB meric acenaphthylene. Number Name Date A p yi n comprising l) hOmopoly' 2 317 7 m A n 27 1943 meric acenaphthylene having a molecular weight of from 150,000 to 341,000 when measured by the 0 OTHER REFERENCES osmotic pressure method, and (b) as a plasticizer Campbell et a1" mm m Am Chem, Soc therefor alphe-methylnaphtlmlen Y 58, 1051-2, (1936) abstractedin Chem. Abstr. 30,

6. A composition of matter comprising (a) 5215 (1933) homopolymeric acenaphthylen having a, molecn m Handbuch der orgamsche c ular weight of from 150,000 to 341,000 when measio" v page 299 (1930) by the Pressure methoda1M1 (b) as Beilstein, Handbuch der organische Chem, vol. a, plasticizer therefor an eutectic mixture of 111- v page 530 (1943) phenyl and diphenyl oxide. Dziewonskl et 91., abet. in Chem. abstr. 18, 982

HARRY 1". mm 924 RALPH G. FLOWERS. 1

REFERENCES CITED The following references are of record in the me of this patent: 

1. THE METHOD WHICH COMPRISES PASSING BORON TRIFLUORIDE THROUGH A SOLUTION OF ACENAPHTHYLENE AT A TEMPERATURE RANGING FROM 0* TO -50*C., AND ADDING A NON-SOLVENT TO THE RESULTING SOLUTION THEREBY TO OBTAIN A HIGH MOLECULAR WEIGHT POLYMER OF ACENAPHTHYLENE HAVING A MOLECULAR WEIGHT BETWEEN 150,000 AND 341,000 WHEN MEASURED BY THE OSMOTIC PRESSURE METHOD. 